Anna Góralska

Septoglomus jasnowskae and Septoglomus turnauae, two new species of arbuscular mycorrhizal fungi (Glomeromycota)

Phylogenetic analyses of SSU-ITS-LSU nrDNA sequences and morphological studies of spores and mycorrhizae confirmed our supposition of finding two new species of arbuscular mycorrhizal fungi of the genus Septoglomus in the phylum Glomeromycota. Morphologically, the first species, named S. jasnowskae, is distinguished by its pale yellow to brownish yellow, small spores with a 2-layered spore wall, of which the colourless outer layer 1 stains dark in Melzer’s reagent and layer 2 is laminate. The spores usually arise in loose clusters. The structures most distinguishing S. turnauae are its two coloured laminate layers in the 4-layered spore wall. In the field S. jasnowskae was associated with roots of Ammophila arenaria and an unrecognized plant species colonizing maritime dunes of the Mediterranean Sea near Thessalonica (Greece) and Calella (Spain), respectively, and S. turnauae formed mycorrhiza with a Cistus sp. (Cistaceae) growing in the soil of a mine located in Sulcis-Iglesiente, SW-Sardinia, Italy. In single-species cultures with Plantago lanceolata as host plant, the mycorrhiza of S. jasnowskae consisted of arbuscules, hyphae and vesicles, and that of S. turnauae comprised arbuscules and hyphae only.

Spore-based study of arbuscular mycorrhizal fungi of semiarid sandy areas in Hungary, with Diversispora jakucsiae sp. nov.

We studied the diversity of arbuscular mycorrhizal fungi (AMF) in semiarid sandy areas of the Great Hungarian Plain representing the westernmost of the Eurasian steppe belt. AM fungal spores were extracted (i) directly from soils collected around 30 Juniperus communis trees of three sampling sites and (ii) from pot trap cultures established with soils from those samples. Altogether spores of 31 AMF species belonging to 15 genera were identified from the field and pot-culture samples. Three taxa could be identified only on the genus level. During the study, one fungus showed a unique combination of morphological characters. Molecular phylogenetic analyses of SSU, ITS, and LSU regions of the nrDNA positioned the fungus in the genus Diversipora and confirmed its novelty when compared with all Diversipora spp. species sequenced to date. This fungus is here described as D. jakucsiae sp. nov.

Three new arbuscular mycorrhizal Diversispora species in Glomeromycota

Morphological observations of spores and mycorrhizal structures of three arbuscular mycorrhizal fungi (Glomeromycota) prompted, and subsequent phylogenetic analyses of SSU–ITS–LSU nrDNA sequences confirmed, that they are undescribed species of the genus Diversispora. Morphologically, the first species, here named D. varaderana, is most distinguished by its relatively small (≤90 μm diam when globose) and yellow-coloured spores with a simple spore wall consisting of two layers, of which layer 1, forming the spore surface, is short-lived and usually completely sloughed in most spores. The distinctive features of the second species, D. peridiata, are the occasional formation of spores in clusters and peridium-like hyphae covering the clusters and single spores, and especially the permanent and relatively thick spore wall layer 1, which is the only coloured component of the two-layered spore wall of the yellow-coloured and relatively small spores (≤100 μm diam). The third species, D. slowinskiensis, is most characterized by its spore wall layer 1 that is the only coloured component of the three-layered spore wall and frequently is covered with blister-like swellings. All the three species were grown in single-species cultures established from spores extracted from trap cultures inoculated with rhizosphere soils of plants growing in maritime sand dunes: D. varaderana from those located near Varadero on the Hicacos Peninsula, Cuba, and the two others from those of the Słowiński National Park, northern Poland.

Sacculospora felinovii, a novel arbuscular mycorrhizal fungal species (Glomeromycota) from dunes on the west coast of India

During an arbuscular mycorrhiza fungal spore survey on a primary coastal sand-dune system in Goa on the west coast of India, entrophosporoid spores tightly covered with a dense hyphal mantle were recovered. When intact, the spores, at first sight, seemed to be identical in morphology to those of Sacculospora baltica (originally described as Entrophospora baltica) extracted from Polish maritime sand dunes and, to date, the sole member of the recently described genus Sacculospora in the new family Sacculosporaceae, phylum Glomeromycota. Later detailed morphological studies indicated that both fungi produce two-walled spores but the structure and phenotypic features of components of the outer spore wall in the novel fungus differ considerably from those of S. baltica. Differences between the fungi were subsequently confirmed in the phylogenetic analysis of SSU–ITS–LSU nrDNA sequences. Consequently, we describe the novel species as Sacculospora felinoviisp. nov.